Independent Garage Suspects Vanos failure

[Monty84]

Wife reported the car losing power and almost stalling in the morning, i drove in the evening and was fine, this happened on two occasions.  last time she told me about it i had a drive up to the petrol station and while sat in the cue, a extremely loud knocking began to come from the front end, around the oil filler cap area.  sounds like the timing chain is knocking and rattling about.

drove home steadily and parked it up, checked oil level and water, all ok.  water pipework was solid with pressure.  let the pressure release and topped a little oil just to bring it right.

started again when cold, same knocking noise from front of engine and decided to get it to the indy garage i trust.  They are a MAN service centre and are reputable while servicing HGV and LGV's they also do work on cars.
they have had a look over and believe the vanos has failed.  quoted £1650 in parts and labour of around 16 hours comes to £2800 with VAT.

Vehicles a 4.6 V8 with 82000 on the clock, i love the car but don't think its worth it.
is there anything else it could be that could cause this issue, that i could get checked to rule out the vanos?

[Monty84]

does anybody think it would be worth while trying a replacement vanos solenoid or changing both?  would this cause knock if they had failed.  also stalled at low revs on way to garage, but didn't drive too bad when above 1000rpm, assume slack taken up at this point.

[henrym3]

Doesn't sound like Vanos failure to me, especially at that mileage, sounds more like timing chain guides. I would be tempted to take it to an Indy or someone who is more familiar with these vehicles and this problem in particular. The cheap way to confirm guides is to drop the oil and remove the sump, If the guides have gone the black plastic bits will be laying in the sump. If it is the guides you'll be quoted similar money

[gchristofi]

Agree with Henry.  I've come across a few 4.6 owners who suffered snapped chains.

[IanP]

It's the guides and/or tensioners

[Greydog]

I had a sticking Vanos solenoid it caused a misfire on cold start not a rattle. I would say if you have a rattle and loss of power it's the chain guides and possibly the chain has slipped.
It's not a good design by BMW all the V8's are prone, more a case of when not if in my opinion.

[Monty84]

As much as I love the car I think this time it's just too much to spend repairing for me.  Will put her up for sale and hope someone with the skill and time purchases her and brings her back to life. Gutted.

[henrym3]

Even I'm gutted to hear that this 84k machine may end up getting sold in bits. Such a pity cos it could probably be fixed for under £400 if you didn't count labour.

[Greydog]

It would be interesting to know how many 4.6 is are actually still running against how many were sold?
Maybe I will keep mine and lay it up who knows it may appreciate in value due to rarity? Had I not had a warranty it would be in bits by know.

[henrym3]

I'd love to know why some of the guides go at (like Monty84)82k my sons 4.4 at 120k and some way beyond that. Is it short journeys (whats a short journey) lack of oil changes, cheap oil, wrong oil. One ends up being paranoid about this problem. I have, on my last oil change dropped the sump to look for bits. I mean, who the hell does that.

[X5Sport]

[quote="Greydog"]
It would be interesting to know how many 4.6 is are actually still running against how many were sold?
Maybe I will keep mine and lay it up who knows it may appreciate in value due to rarity? Had I not had a warranty it would be in bits by know.
[/quote]

522 still licenced, 89 on SORN.  Peak licences in the U.K. was 844 in Q4 2003.  Almost 2/3rds still on the road end of September.

More than 7,000 3.0D were on the register in Q4 2003.  Hard to gauge how many are left, but it is well over 4K.

[themoog]

I had my guides done a few months ago when it failed. Bartlett autos in Huntingdon £1900. I would defo get it fixed as the car is worthless as it is.

[Monty84]

[quote="henrym3"]
Even I'm gutted to hear that this 84k machine may end up getting sold in bits. Such a pity cos it could probably be fixed for under £400 if you didn't count labour.
[/quote]

Unfortunately i have been told around £1300 for parts for guides? am i missing something here?

[Greydog]

When my engine failed last Christmas it was at 91k. The guy who stripped and rebuilt the engine is an ex BMW tech who now runs his own busines as a BMW Porsche specialist. The failure was sudden loss of oil pressure fortunately I was heading into a service area when it happened and I shut down immediately.

The engine was removed from the car and stripped for inspection by my warranty company it was unclear whether the chain guides failed blocking the oil pump or the oil pump failed causing the guides to go (the guy rebuilding it was of the opinion it was the guides at fault as he has seen many). The design is not good with the timing chain running in plastic guides with a small spring assisted hydraulic tensioner.
I inspected the plastc bits recovered from the sump and they were very brittle, the view of the engine man which I support is the engine at some point has run hot or overheated, after many heat cycles the plastic is brittle worse the spring in the tensioner has had the same heat cycle treatment and losses some tension.

Once this has happened it is only a matter of time until it lets go "not if but when" after my engine was rebuilt I have fitted a pre-oiling system to ensure full oil pressure is present at start up.

What should be a really good engine is spoiled by some cheap "production engineering" BMW are not alone Audi and others have the plastic guide issue as well.

As for cost the full parts list for mine was very long and came in at £2100 but included a new oil pump all bearings ring sets gaskets (lots of gaskets) labour was around 40 hrs giving a final bill of £5500 inc VAT
The warranty picked up all the labour plus 50% of parts due to the cars age, without the warranty it would have been scrapped.

So £1300 for parts doesn't sound out of line to me if you are able to do the work yourself you will save a huge chunk on labour cost and by shopping around you may save on parts. 20 years ago I would have put the car in my workshop and done the work myself now in my 70's my body doesn't have the same enthusiasm as my brain, so some things I do and others like this I am happy to leave to the young ones (with a little help from the Warranty).

[Greydog]

[quote="X5Sport"]
[quote="Greydog"]
It would be interesting to know how many 4.6 is are actually still running against how many were sold?
Maybe I will keep mine and lay it up who knows it may appreciate in value due to rarity? Had I not had a warranty it would be in bits by know.
[/quote]

522 still licenced, 89 on SORN.  Peak licences in the U.K. was 844 in Q4 2003.  Almost 2/3rds still on the road end of September.

More than 7,000 3.0D were on the register in Q4 2003.  Hard to gauge how many are left, but it is well over 4K.
[/quote]

Interesting numbers Richard BMW definatly make a better straight six (diesel or petrol) so I would suspect that Gearbox failure or accident damage would claim more of these than engine failure.
The V8's however just seem fragile by comparison in both the Range Rover and the X5

Could be 521 possibly now depending on Monty84's decision, maybe I will keep it